ABSTRACT The primary objective of surgical therapy for the treatment of patients with any cancer is to remove all cancer cells from within the body, with the secondary objective of maintaining organ function. The primary pathological metric used to rate the success of a surgical procedure is evaluation of the surgical margin of the resected tissue specimen, post-operatively. This typically involves cutting the tissue into sections and microscopically exploring these tissue samples for the presence of cancer cells at the margins. Cancer cells noted at the margins represent Positive Surgical Margins (PSMs) and suggest that cancer cells were left in the body following the procedure. As a result, patients with PSMs are often exposed to noxious additional procedures to eradicate the cancer cells left behind including radiation, chemical, hormonal, and additional surgical therapy; these all have adverse morbidities that decrease a patient's quality of life. No clinical protocols are routinely used to intraoperatively assess surgical margin status during surgical procedures. Instead, margins are evaluated through microscopic assessment of the tissue following the procedure, when it is too late to provide additional surgical intervention. We aim to develop an intraoperative device able to assess surgical margin status so that the surgeons can extract additional tissues in real-time and ultimately decrease the rates of PSMs. While our technology can be applied for most cancer surgeries, we are focusing our commercialization efforts on prostate and breast cancer as these are the highest incidence and cause of death for men and women, respectively, and because patients with PSMs following these procedures have a much higher rate of recurrence than patients that have negative surgical margins. We have previously shown that the electrical impedance (a property that describes how easily electrical current passes through a tissue) of tissue is sensitive to a tissue's cellular arrangement and can be used to distinguish cancer from benign tissue in both prostate and breast. We have developed a prototype flexible endoscopic device capable of sensing electrical impedance of tissue during radical prostatectomy procedures for use in Machine Learning-based tissue classification and Electrical Impedance Tomography (EIT) imaging techniques. This device makes intraoperative focal measurements of margin status. Here we aim to take the significant step of constructing an optimized EII device that can be deployed either laparoscopically (e.g. prostate surgery) or in open procedures (e.g. breast surgery) to provide an accurate method of intraoperatively identifying positive surgical margins. We aim to develop this device and evaluate the technology in an ex vivo study of human prostates to confirm device functionality. By the end of this program we intend to have developed a low-cost, single use probe that can be deployed for intraoperative surgical margin assessment. In follow-on Phase II funding, we will focus our technical design efforts on developing a custom data acquisition system and visualization platform and preparing for an IDE submission to the FDA.